Dual-band circularly polarized dielectric resonator antenna

By choosing adequate shorted section of an annular slot, CP operation of the slot-coupled DRA has been implemented. From the results obtained, by changing the slot radius, a DR element can meet wide frequency band selections. And, using a pair of concentric C-shaped slots to excite dual-band CP operation has also been successfully implemented. The experimental results show good CP radiation characteristics for the two operating bands of the proposed design. Finally, it should be noted that the frequency ratio of the two operating modes shown here is /spl sim/1.67. By varying the two concentric C-shaped slots radius and fine-adjusting the shorted section flared angle and tuning stub length, different frequency ratios of the proposed dual-band CP operation are expected to be achieved.